It is known that occasionally it is necessary to keep concentrated substances, in general in the form of a liquid or a powder, which are dissolved in a solvent consisting generally of water only at the time of use. Typically this occurs, for instance in the domestic field to prepare fertilizin solutions, herbicides or similar solutions.
The fact that it is possible to place these substances in sealed containers permits first of all to be able to fill with the desired solution a bottle or a similar receptacle only when there is the actual necessity to use the solution. Further several substances mentioned hereinabove have a tendency to degrade gradually if they are placed in solution while they maintain essentially unaltered their quality for periods of time which are also extremely long if they are maintained in an essentially sealed container.
According to the prior art a container comprises a pair of essentially hollow members which have cylindrical symmetry, one of which is disposed within the other, and which are assembled with mechanical interference corresponding to two areas of different diameter. These members define internally in the space between them a sealed chamber in the shape of a cylindrical crown corresponding to their exact and reciprocal axial position. This container is particularly capable to be placed in a place corresponding to the upper mouth of a bottle.
There is provided the possibility of causing the internal member to slide axially with respect to the external member which on the contrary remains fixed with respect to the mouth mentioned hereinabove, an arrangement which may be easily achieved at the time the metal ring of an atomizer is screwed, which is capable to cause the solution in the bottle to exit. This determines the exit from the chamber mentioned hereinabove of the concentrated substance and consequently its fall in the bottle causing the substance to mix with the solvent which fills the latter.
In this manner, the individual using the bottle may limit himself to acquire the receptacle containing the liquid which is necessary, which presents extremely limited dimensions in view of the high concentration of the content because it is possible to apply in general the device to any bottle, any receptacle and similar devices.
It is also clear that in view of the small space occupied by a single container, it is very useful and simple for the individual using the container to acquire and to maintain a plurality of the containers, without mentioning that also for the industry which produces the concentrated substance, it is simpler to sell concentrated substances enclosed in a small container rather than selling the substance contained in bottles or similar devices of large dimensions.
The container described in the above mentioned patent does not offer, however, sufficient guaranty of the seal with respect to the exit of the substance between the two elements having cylindrical symmetry in view of the small size of the surfaces which interfere corresponding to the area of greater diameter.